Apparatus for controlling the rotary motion of a printing roller



Nov. 9, 1965 w. RITZERFELD ETAL 3,216,351

APPARATUS FOR CONTROLLING ROTARY MOTION OF A PRINTING ROLLER Filed May 31, 1962 2 Sheets-Sheet 1 .70 van for; ,-ud. magma Eenm-d. lf eqdd Nov. 9, 1965 APPARATU Filed May 31, 1962 W. RITZERFELD ETAL 5 FOR CONTROLLING ROTARY MOTION OF A PRINTING ROLLER 2 Sheets-Sheet 2 United States Patent 3,216,351 APPARATUS FOR CONTRGLLING THE ROTARY MOTIGN OF A PRINTHNG ROLLER Wilhelm Ritzerfeld, Schorlemer Allee 14, Berlin-Dahlem, Germany, and Gerhard Ritzerfeld, Franzensbader Strasse 21, Berlin-Grunewald, Germany Filed May 31, 1962, Ser. No. 1%,100 Claims priority, application Germany, June 5, 1961, R 30,461 9 Claims. (Cl. 101235) The present invention relates to an apparatus for controlling the rotary motion of a printing roller, and more particularly to an apparatus for stopping a duplicating roller in a selected angular position in which a copy sheet is supplied to the duplicating roller.

In machines of this type either a single copy sheet is supplied by the operator to the printing roller while the same is stopped in a selected angular position, or the copy sheets of a stack are successively supplied by an automatic operation to the printing roller after each revolution of the printing roller.

In any event, it is desirable that the printing roller automatically stops in such a position that a printing form on the printing roller is properly located relative to the guide means and transporting means by which the copy sheet is supplied to the printing roller. This permits the feeding of the copy sheet by an operator without requiring the operator to get up from his seat, and to turn or adjust the printing roller to a desired angular position.

In known printing machines of this type, one revolution couplings are provided for connecting the drive motor with the printing roller, so that the printing roller is stopped after each revolution by automatic release of the coupling means by a cam rotating with the printing roller. However, these constructions have certain disadvantages, since they are rather complicated, and cause very hard impacts of the rotating parts on the stationary parts when the printing cylinder is stopped.

Electro-rnagnetic couplings have also been used in prior art constructions. However, since substantial masses have to be stopped, very powerful electro-magnetic couplings are necessary which are expensive, and nevertheless incapable of precisely stopping the printing roller in the desired selected position.

It is one object of the present invention to overcome the disadvantages of known constructions for controlling the rotary motion of a printing roller, and to provide an inexpensive, reliably operating apparatus assuring precise stopping of the printing roller, or of a corresponding rotary element, in a desired position.

Another object of the present invention is to drive a printing roller through one revolution, and to stop the printing roller after each revolution in an exactly determined angular position without a one revolution coupling.

Another object of the present invention is to drive the printing roller directly by an electric motor, and to automatically de-energize and brake the motor in a selected angularposition of the printing roller.

Another object of the present invention is to provide an arrangement for controlling the rotary motion of the printing roller which permits the start of the printing roller only when a copy sheet is printing roller.

With these objects in view, one embodiment of the present invention comprises a rotary element, such as a printing or duplicating roller; an electric motor for driving the printing roller; brake means for braking the motor and the printing roller; and switch means which are operatively connected with the printinf roller to disconproperly supplied to the 3,216,351 Patented Nov. 9, 1965 nect the motor from its power source and to actuate the brake means when the printing roller arrives in a selected angular position.

In the preferred embodiment of the invention, a cam means rotating with the printing roller opens a normally closed stationary stop switch means in the selected angular position of the printing roller. The stop switch means simultaneously de-energizes the motor, and energizes electro-magnetic operating means of the brake means to release the brake means which are urged by a spring to move to a braking position.

Since the stop switch means is open in the selected position, a switch is connected in parallel with the stop switch means, and in series with the electro-magnetic operating means of the brake means and with the motor, so that the machines can be started in the position in which the printing roller is automatically stopped. When the switch is closed, the motor turns until the cam means on the printing roller has released the stop switch means, so that the same closes and connects the motor into the circuit. Thereupon, the switch by which the startof the mot-or was effected, can be released.

Instead of one switch for starting the motor, several switches may be provided. A first manually operated switch is closed only as long as it is depressed by the operator, and the operator releases this start switch as soon as the printing roller has turned far enough out of its stopped position to permit closing of the stop switch means. Another manually operated switch is adapted to remain closed between a first and second actuation, and is also connected in series with the motor, so that the same runs only between the first and the second actuation of this start switch which shunts the stop switch means when the stop switch means is opened by the cam means during each revolution of the printing roller.

In order to prevent that the machine is started with out a copy sheet being supplied to the printing roller, a control switch is also connected in series with the motor, and with the manually operated switches. The control switch is closed when a copy sheet is placed on the guide and transporting means by which it is fed to the printing roller. A bulge formed in the copy sheet may be used for operating the control switch, or the weight of a stack of copy sheets will have the same effect.

In the preferred embodiment of the invention, scissorlike brake members are urged by a spring means to a braking position engaging a brake disc secured to a shaft of the motor. A coil is secured to one of the brake members, and the armature cooperating with the coil is secured to the other of the brake members. The armature and the coil constitutes the electromagnetic operating means for the brake.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

FIG. 1 is a fragmentary schematic cross-sectional view illustrating the arrangement of the present invention as applied to a rotary duplicating machine, and including a schematic diagram illustrating electric circuit of the preferred embodiment of the invention; and

FIG. 2 is a fragmentary schematic plan view of the embodiment illustrated in FIG. 1.

Referring now to the drawings which illustrate a conventional duplicating machine provided with the arrangement of the present invention, a printing or duplicating roller 1 rotates about the axis of a shaft 2 and cooperates with a counter roller 32 whose shaft 33 is mounted on the frame of the machine. Guide means 17 are provided for guiding a copy sheet 16 toward a pair of transporting and moistening rollers 11 and 14 by which the copy sheet 16 is transported toward the bight formed between the printing roller 1 and the counter roller 32.

Shaft 2 of printing roller 1 carries a gear 3 which is driven through a gear belt or chain 31 from another gear 24 mounted on shaft of an electric motor 21.

Motor shaft 25 carries a brake disc which can be gripped between a pair of scissor-like brake members 35, 36. Spring means 23 connect the brake members and urge the same to the braking position engaging the brake disc 30. The brake means includes electro-magnetic operating means by which the brake members are operated, and comprising a coil 28 mounted on one of the brake members, and an armature cooperating with the coil 28 and fixedly connected to the other brake member. The arrangement is such that energization of the electro-magneti-c operating means 28 will cause the brake members 35, 36 to move apart against the action of spring means 23, and to release the brake disc 30.

A first actuating means in the form of a cam 4 is secured to gear 3 and rotates with printing roller 1. On a wall 34 of the frame of the machine, a lever 6 is In-ount ed for turning movement about the pivot pin 5, and carries a roller 8 cooperating with cam 4. Consequently, lever 6 is raised once during each revolution of the printing roller to actuate a stop switch means 7 which is normally closed, but opens when actuated. The cam means 4 is positioned in such a manner that stop switch means 7 is opened in a selected angular position of the printing roller in which a copy sheet is properly positioned relative to the printing roller when supplied to the same.

On the housing of the machine, two manually operated switches 9 and 10 are provided. Switch 10 is normally opened, and is closed only as long as it is depressed by the operator. Switch 9 is of the type which closes upon a first actuation by the operator, and remains closed until the operator actuates switch 9 a second time. The manually operated switches 9 and 10 are used for starting the motor, and are connected in series with motor 21, and also with a control switch 19. Control switch 19 has a feeler arm projecting through a hole in the guide table means 17, so that a copy sheet 16 placed on the guide table means 17, and urged against the pair of rollers 11,

14 will form a bulge pressing against the feeler arm of If a stack of,

switch 19 whereby switch 19 is closed. copy sheets 38 is placed on the feeler arm, control switch 19 is also closed. A feeding member 39 including a roll resting on the stack 38 is automatically reciprocated in the conventional manner for feeding the top copy sheet to the roller pair 11, 13.

The electric circuit of the arrangement is connected to a source of power and includes a grounded automatic interrupter switch 18. Control switch 19 is connected in series with the manually operated switches 9 and 11) which are connected in parallel with each other. Switches 9, 10 and 19 are connected in series with motor 21 whose other terminal is connected to the source of power, and also to a condenser 20. Coil 28 of the electro-magnetic operating means of the brake is connected in parallel to motor 21. Stop switch means 7 is connected in parallel with switches 9, 10 and 19.

The apparatus is operated as follows:

The printing roller 1 is in the illustrated posit-ion in which actuating cam 4 engages actuating arm 6 so that stop switch means 7 is open, which caused stopping of the machine during the preceding operation. Consequently, the printing roller 1 is in a desired position in which the holding means holds a printing form on the peripheral surface of printing roller 1 in a certain position relative to transporting rollers 11, 14 and counter roller 32. Start switch 9 is operated, and remains closed until again actuated by the operator. When a copy sheet 16 is now placed on the guide table 17, and urged against rollers 11, 14, a bulge forms which depresses the feeler lever of switch 19, and closes the same so that the circuit of the electro-magnetic operating means 28, and of motor 21 is closed, so that the brake members 35, and 36 are moved apart against the action of spring 23 permitting the energized motor to start its rotation. Printing roller 1 also starts turning since it is driven through the transmission 24, 31, 3. Transporting and moistening rollers 11, 14 are driven through gear means, not shown, from motor 21 so that copy sheet 16 is transported toward the bight between printing roller 1 and counter-roller 33. Due to the initial turning movement of printing roller 1, actuating cam 4 releases the actuating arm 6, so that stop switch 7 closes and bridges the actuated start switch 9. Since the circuit is now completed by the closed stop switch 7, printing roller 1, counter pressure roller 32, rollers 11 and 14 will continue to rotate although switch 119 may open, until cam 4 again engages arm 6 of stop switch 7 to open stop switch 7 after a single revolution. By suitably positioning the actuating cam 4-, the initial home position of printing roller 1 was so selected that the transported copy sheet 16 is gripped between the printing form h ld by holding means 40 and the counter roller 33 in the proper printing position in which an imprint is made by the printing form on the copy sheet during further rotation of the printing roller. After a single revolution of the printing roller, stop switch 7 is opened by cam 4, and since no copy sheet is located on the feeler lever of switch 19, switch 19 is also open so that motor 21 is disconnected from the power source by the open switches 7 and 19. The rotor of motor 21 tends to continue its rotation due to its inertia, but spring 23 rapidly closes the brake members 35, 36 so that they engage brake disc 30 and stop the motor, and thereby the printing roller which is positively connected to the shaft 25 of motor 21 by the transmission means 3, 31, 24. Thus, printing roller 1 is stopped after one revolution in the desired selected position in which feeding of a copy sheet will result in a correctly placed imprint on the copy sheet.

-If a stack of copy sheets 38 is placed on the feeler lever of switch 19, the same is held closed. In this event, start switch 10 is operated so that the circuit of motor 21 is closed and the printing roller starts to rotate until earn 4 permits the closing of stop switch 7. Thereupon, stop switch 10 can be released by the operator, since the circuit of the motor and the brake means is completed by stop switch 7. After each revolution, printing roller 1 is stopped by the actuated stop switch 7 in the desired selected position so that a new copy sheet can be manually or automatically supplied. When the last copy sheet has been supplied, the feeler arm of switch 19 will open switch 19. The printing roller will stop when arriving in its home position in which cam 4 opens stop switch means 7.

It is evident that the arrangement of the brake means can be reversed, so that the brake means is closed when the electro-magnetic operating means 28 is energized, while the brake means is normally open under the action of a spring. It is also possible to mount the stop switch 7 for rotation with printing roller 1, and to provide a stationary actuating cam for opening stop switch means 7 after each revolution of printing roller 1 in the selected home position of the printing roller.

-It will be understood that each of the elements described above, or two or more together, may also find a useful Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. A printing machine, comprising in combination, a rotary printing element; an electric motor means in direct driving connection with said rotary printing element so that the same rotates as long as said motor means operates and stops when said motor means stops; circuit means for connecting said motor means to a source of electric power and including a sheet actuated control switch, a manually operated switch, stop switch means and electrically controlled brake means for braking said motor means and said rotary printing element, said stop switch means being operatively connected with said rotary printing element to disconnect said motor means from said source and to actuate said brake means in a selected angular position of said rotary printing element whereby said rotary printing element is stopped in said selected angular position; and means for guiding a copy sheet to said rotary printing element in said selected angular position and being positioned relative to said control switch so that said control switch is actuated by a copy sheet guided toward said rotary printing element.

2. In a printing machine, in combination, a rotary printing element; an electric motor means in direct driving connection with said rotary printing element so that the same rotates as long as said motor means operates and stops when said motor means stops; circuit means for connecting said motor means to a source of electric power and including a sheet actuated control switch, a manually operated switch, adapted to be closed only while manually actuated, and another manually operated switch adapted to remain closed after an actuation until again manually actuated, stop switch means and electrically controlled brake means for braking said motor means and said rotary printing element, said stop switch means being operatively connected with said rotary printing element to disconnect said motor means from said source and to actuate said brake means in a selected angular position of said rotary printing element whereby said rotary printing element is stopped in said selected angular position; and means for guiding a copy sheet to said rotary printing element in said selected angular position and being positioned relative to said control switch so that said control switch is actuated by a copy sheet guided toward said rotary printing element.

3. A printing machine as set forth in claim 1 wherein said sheet actuated control switch is located in the region of said guide means and is operated by a copy sheet placed on said guide means.

4. A- printing machine as set forth in claim 3 and including means for forming a bulge in a copy sheet on said guide means and located so that the bulge engages said sheet actuated control switch and actuates the same.

5. In a printing machine, in combination, a rotary printing roller; guide means for guiding a copy sheet toward said printing roller; holding means for attaching a copy sheet to said printing roller and being located opposite said guide means in a selected angular position of said printing roller; an electric motor means directly connected with said printing roller for rotating the same so that the same rotates as long as said motor means operates and stops when said motor means stops; an electric brake means for braking said motor means and said printing roller; circuit means for connecting said motor means and said brake means to a source of electric power; stationary first actuating means; second actuating means connected to said printing roller for synchronous rotation therewith, one of said actuating means including a stop switch means connected into said circuit means, said first actuating means cooperating with said second actuating means in said selected position of said printing roller to operate said stop switch means so that said motor means is disconnected from said source and said electric brake means is actuated to stop said printing roller in said selected position so that a copy sheet can be supplied to said printing roller in a desired relative position to said holding means; and a manually operated start switch connected in series with said motor means so that upon actuation of said start switch said motor means starts to rotate said printing roller in said selected position until said stop switch means connects said motor means to said source so that said motor means continues to rotate after said start switch is manually released; and a second manually operated start switch adapted to remain closed between a second and a first actuation and being connected in series with said motor means.

6. In a printing machine, in combination, a rotary printing roller; guide means for guiding a copy sheet toward said printing roller; holding means for attaching a copy sheet to said printing roller and being located opposite said guide means in a selected angular position of said printing roller; an electric motor means directly connected with said printing roller for rotating the same so that the same rotates as long as said motor means operates and stops when said motor means stops; an electric brake means for braking said motor means and said printing roller; circuit means for connecting said motor means and said brake means to a source of electric power; stationary first actuating means; second actuating means connected to said printing roller for synchronous rotation therewith, one of said actuating means including a stop switch means connected into said circuit means, said first actuating means cooperating with said second actuating means in said selected position of said printing roller to operate said stop switch means so that said motor means is disconnected from said source and said electric brake means is actuated to stop said printing roller in said selected position so that a copy sheet can be supplied to said printing roller in a desired relative position to said holding means; a manually operated start switch connected in series with said motor means so that upon actuation of said start switch said motor means starts to rotate said printing roller in said selected position until said stop switch means connects said motor means to said source so that said motor means continues to rotate after said start switch is manually released; and a second manually operated start switch adapted to remain closed between a second and a first actuation and being connected in series with said motor means; and a control switch located in the region of said guide means and being connected in series with said first and second start switches and said motor means and adapted to be operated by copy sheet placed on said guide means so that rotation of said printing roller can only be started by operation of said first or second start switch and by placing a copy sheet on said guide means.

7. In a printing machine, in combination, a rotary printing roller; guide means for guiding a copy sheet toward said printing roller; holding means for attaching a copy sheet to said printing roller and being located opposite said guide means in a selected angular position of said printing roller; an electric motor means directly connected with said printing roller for rotating the same so that the same rotates as long as said motor means operates and stops when said motor means stops; an electric brake means for braking said motor means and said printing roller and including an electro-magnetic means, and mechanical brake means including spring means; circuit means for connecting said motor means and said electro-magnetic means to a source of electric power; stationary first actuating means; second actuating means connected to said printing roller of synchronous rotation therewith, one of said actuating means including a stop switch means connected into said circuit means, said first actuating means cooperating with said second actuating means in said selected position of said printing roller to operate said stop switch means so that said motor means is disconnected from said source and said electric brake means is actuated to stop said printing roller in said selected pos tion so that a copy sheet can be supplied to said printing roller in a desired relative position to said holding means; a manually operated start switch connected in series with said motor means so that upon actuation of said start switch said motor means starts to rotate said printing roller in said selected position until said stop switch means connects said motor means to said source so that said motor means continues to rotate after said start switch is manually released; and a second manually operated start switch adapted to remain closed between a second and a first actuation and being connected in series With said motor means; and a 20 control switch located in the region of said guide means and being connected in series with said first and second start switches and said motor means and adapted to be operated by copy sheet placed on said guide means so that rotation of said printing roller can only be started by operation of said first or second start switch and by placing a copy sheet on said-guide means.

8. An arrangement as set forth in claim 7 wherein said spring means of said brake means urge said brake means to a braking position; wherein said stop switch means is normally closed, and is opened in said selected position of said printing roller; wherein said stop switch is connected in series with said motor means and with said electro-magnetic means; wherein said electro-magnetic means and said motor means are connected in parallel; wherein said first and second start switches are connected in parallel with said stop switch means and are normally open; wherein said control switch is connected in series with said first and second start switches and is normally open.

9. An arrangement as set forth in claim 7 wherein said first actuating means includes said stop switch means, and wherein said second actuation means is a 'cam connected to said printing roller for rotation therewith.

References Cited by the Examiner UNITED STATES PATENTS 766,117 7/04 Rundle 188171 2,352,802 7/44 Ryan et a1 l01--235 2,518,221 8/50 Camphouse 101132.5 2,577,663 12/51 Owens 318275 X 2,645,174 7/53 Levin 101132 2,683,413 7/54 Muller 101-235 2,753,502 7/56 Kylin 318-275 X 2,769,948 11/56 Elliott 3 l8-275 2,812,484 11/57 Westfelt 318-275 X EUGENE R. CAPOZIO, Primary Examiner. 

1. A PRINTING MACHINE, COMPRISING IN COMBINATION, A ROTARY PRINTING ELEMENT; AN ELECTRIC MOTOR MEANS IN DIRECT DRIVING CONNECTION WITH SAID ROTARY PRINTING ELEMENT SO THAT THE SAME ROTATES AS LONG AS SAID MOTOR MEANS OPERATES AND STOPS WHEN SAID MOTOR MEANS STOPS; CIRCUIT MEANS FOR CONNECTING SAID MOTOR MEANS TO A SOURCE OF ELECTRIC POWER AND INCLUDING A SHEET ACTUATED CONTROL SWITCH, A MANUALLY OPERATED SWITCH, STOP SWITCH MEANS AND ELECTRICALLY CONTROLLED BRAKE MEANS FOR BRAKING SAID MOTOR MEANS AND SAID ROTARY PRINTING ELEMENT, SAID STOP SWITCH MEANS BEING OPERATIVELY CONNECTED WITH SAID ROTARY PRINTING ELEMENT TO DISCONNECT SAID MOTOR MEANS FROM SAID SOURCE AND TO ACTUATE SAID BRAKE MEANS IN A SELECTED ANGULAR POSITION OF SAID ROTARY PRINTING ELEMENT WHEREBY SAID ROTARY PRINTING ELEMENT IS STOPPED IN SAID SELECTED ANGULAR POSITION; AND MEANS FOR GUIDING A COPY SHEET TO SAID ROTARY PRINTING ELEMENT IN SAID SELECTED ANGULAR POSI- 